[PATCH 5.15 086/177] ice: Use div64_u64 instead of div_u64 in adjfine

From: Greg Kroah-Hartman
Date: Mon Dec 20 2021 - 09:57:50 EST


From: Karol Kolacinski <karol.kolacinski@xxxxxxxxx>

[ Upstream commit 0013881c1145d36bf26165bb70fdd7560a5507a3 ]

Change the division in ice_ptp_adjfine from div_u64 to div64_u64.
div_u64 is used when the divisor is 32 bit but in this case incval is
64 bit and it caused incorrect calculations and incval adjustments.

Fixes: 06c16d89d2cb ("ice: register 1588 PTP clock device object for E810 devices")
Signed-off-by: Karol Kolacinski <karol.kolacinski@xxxxxxxxx>
Tested-by: Gurucharan G <gurucharanx.g@xxxxxxxxx>
Signed-off-by: Tony Nguyen <anthony.l.nguyen@xxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
drivers/net/ethernet/intel/ice/ice_ptp.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/net/ethernet/intel/ice/ice_ptp.c b/drivers/net/ethernet/intel/ice/ice_ptp.c
index d1ef3d48a4b03..9df546984de25 100644
--- a/drivers/net/ethernet/intel/ice/ice_ptp.c
+++ b/drivers/net/ethernet/intel/ice/ice_ptp.c
@@ -459,7 +459,7 @@ static int ice_ptp_adjfine(struct ptp_clock_info *info, long scaled_ppm)
scaled_ppm = -scaled_ppm;
}

- while ((u64)scaled_ppm > div_u64(U64_MAX, incval)) {
+ while ((u64)scaled_ppm > div64_u64(U64_MAX, incval)) {
/* handle overflow by scaling down the scaled_ppm and
* the divisor, losing some precision
*/
--
2.33.0